[Qemu-devel] [PATCH v2 3/8] cutils: Export only buffer_is_zero

[Richard Henderson <rth@twiddle.net>]

Since the two users don't make use of the returned offset,
beyond ensuring that the entire buffer is zero, consider the
can_use_buffer_find_nonzero_offset and buffer_find_nonzero_offset
functions internal.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 include/qemu/cutils.h | 2 --
 migration/ram.c       | 2 +-
 migration/rdma.c      | 5 +----
 util/bufferiszero.c   | 8 ++++----
 4 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/include/qemu/cutils.h b/include/qemu/cutils.h
index 3e4ea23..ca58577 100644
--- a/include/qemu/cutils.h
+++ b/include/qemu/cutils.h
@@ -168,8 +168,6 @@ int64_t qemu_strtosz_suffix_unit(const char *nptr, char **end,
 /* used to print char* safely */
 #define STR_OR_NULL(str) ((str) ? (str) : "null")
 
-bool can_use_buffer_find_nonzero_offset(const void *buf, size_t len);
-size_t buffer_find_nonzero_offset(const void *buf, size_t len);
 bool buffer_is_zero(const void *buf, size_t len);
 
 /*
diff --git a/migration/ram.c b/migration/ram.c
index a3d70c4..a6e1c63 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -73,7 +73,7 @@ static const uint8_t ZERO_TARGET_PAGE[TARGET_PAGE_SIZE];
 
 static inline bool is_zero_range(uint8_t *p, uint64_t size)
 {
-    return buffer_find_nonzero_offset(p, size) == size;
+    return buffer_is_zero(p, size);
 }
 
 /* struct contains XBZRLE cache and a static page
diff --git a/migration/rdma.c b/migration/rdma.c
index 5110ec8..88bdb64 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -1934,10 +1934,7 @@ retry:
              * memset() + madvise() the entire chunk without RDMA.
              */
 
-            if (can_use_buffer_find_nonzero_offset((void *)(uintptr_t)sge.addr,
-                                                   length)
-                   && buffer_find_nonzero_offset((void *)(uintptr_t)sge.addr,
-                                                    length) == length) {
+            if (buffer_is_zero((void *)(uintptr_t)sge.addr, length)) {
                 RDMACompress comp = {
                                         .offset = current_addr,
                                         .value = 0,
diff --git a/util/bufferiszero.c b/util/bufferiszero.c
index 067d08f..0cf8b6e 100644
--- a/util/bufferiszero.c
+++ b/util/bufferiszero.c
@@ -192,9 +192,9 @@ static bool avx2_support(void)
     return b & bit_AVX2;
 }
 
-bool can_use_buffer_find_nonzero_offset(const void *buf, size_t len) \
+static bool can_use_buffer_find_nonzero_offset(const void *buf, size_t len) \
          __attribute__ ((ifunc("can_use_buffer_find_nonzero_offset_ifunc")));
-size_t buffer_find_nonzero_offset(const void *buf, size_t len) \
+static size_t buffer_find_nonzero_offset(const void *buf, size_t len) \
          __attribute__ ((ifunc("buffer_find_nonzero_offset_ifunc")));
 
 static void *buffer_find_nonzero_offset_ifunc(void)
@@ -215,12 +215,12 @@ static void *can_use_buffer_find_nonzero_offset_ifunc(void)
 }
 #pragma GCC pop_options
 #else
-bool can_use_buffer_find_nonzero_offset(const void *buf, size_t len)
+static bool can_use_buffer_find_nonzero_offset(const void *buf, size_t len)
 {
     return can_use_buffer_find_nonzero_offset_inner(buf, len);
 }
 
-size_t buffer_find_nonzero_offset(const void *buf, size_t len)
+static size_t buffer_find_nonzero_offset(const void *buf, size_t len)
 {
     return buffer_find_nonzero_offset_inner(buf, len);
 }
-- 
2.7.4